Back to EveryPatent.com
United States Patent | 5,350,487 |
Ameen ,   et al. | September 27, 1994 |
The present invention relates to methods of etching polyimide from a substrate and to the etched substrates prepared according to such methods. In one embodiment, the present invention provides a method of etching polyimide from a substrate, comprising the steps of: providing a basic bath; ultrasonically agitating said basic bath; exposing said substrate containing polyimide to said basic bath; rinsing said substrate with hot water; optionally repeating the aforementioned steps at least once; and recovering an etched substrate. In another embodiment, the present invention provides a method of etching polyimide from a substrate, comprising the steps of: providing a basic bath; exposing said substrate containing polyimide to said basic bath; rinsing said substrate with hot water; maintaining the high loading capacity of said basic bath after exposure of polyimide to said basic bath, comprising cooling at least a portion of said basic bath thereby precipitating particles and separating the particles from said basic bath prior to reuse of said basic bath; and recovering an etched substrate.
Inventors: | Ameen; Thomas J. (6818 Glencairn Ct., Mentor, OH 44060); Payak; John A. (30050 Euclid Ave., G-8, Wickliffe, OH 44092); Cangelosi; Jerome M. (7817 Richwood Dr., Mentor-on-the Lake, OH 44060) |
Appl. No.: | 057005 |
Filed: | May 3, 1993 |
Current U.S. Class: | 216/83; 216/90; 252/79.5; 257/E23.065 |
Intern'l Class: | B44C 001/22; B29C 037/00 |
Field of Search: | 156/637,639,642,655,659.1,668 134/26,29,34 252/79.5 |
3400027 | Sep., 1968 | Radimer et al. | 156/19. |
3791848 | Feb., 1974 | De Angelo | 117/47. |
3833436 | Sep., 1974 | Hillis et al. | 156/13. |
4426253 | Jan., 1984 | Kreuz et al. | 156/668. |
4428796 | Jan., 1984 | Milgram | 156/637. |
4563242 | Jan., 1986 | Shigemitsu | 156/651. |
4647345 | Mar., 1987 | Polan | 204/13. |
4846929 | Jul., 1989 | Bard et al. | 156/630. |
4857143 | Aug., 1989 | Glenning et al. | 156/668. |
4878991 | Nov., 1989 | Eichelberger et al. | 156/630. |
4911786 | Mar., 1990 | Kindl et al. | 156/659. |
4959121 | Sep., 1990 | Dumas et al. | 156/668. |
4960491 | Oct., 1990 | Youlton | 156/668. |
4976808 | Dec., 1990 | Ogasawara | 156/668. |